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See extensive comments in the sources for more details and examples. New File Drop provides special File List object instead of arrays that were used when passing dropped files to event listeners.

This object is array-like and contains useful methods for filtering, sorting and updating the collection. If value is already an array its copy is returned (so changing value later doesn’t affect the returned clone).

These callbacks receive the same arguments as the target event plus that event’s name in front. Below is a brief description of all methods available on a Drop Handle instance.For this reason Drop Handle automatically facilitates the upload and offers only one event map — all handlers attached to this zone.When given a single non-array parameter returns array of handlers of that particular event.Unlike File API events that let you decide what to do with the file — read, upload or descrad it — was changed according to onchange event.There’s no way to make sure it was populated or retrieve any info about the file — this can only be done by the server which may return something useful in response.